Investments - Schedule of Investments in Fixed Maturity Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value	$ 7,700	$ 8,100
Cost	27,583	22,352
Gross Unrealized Gains	205	7
Gross Unrealized Losses	(17)	(222)
Fair Value	27,771	22,137
U.S. Treasury securities, obligations of U.S. Government agencies and Municipalities
Debt Securities, Available-for-sale [Line Items]
Cost	23,254	21,729
Gross Unrealized Gains	164	7
Gross Unrealized Losses	(17)	(222)
Fair Value	23,401	21,514
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Cost	4,329	623
Gross Unrealized Gains	41	0
Gross Unrealized Losses	0	0
Fair Value	$ 4,370	$ 623

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date.

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